<i>Paranthropus boisei</i> (IMAGE) University of Colorado at Boulder Caption Paranthropus boisei, an ancient human relative that was nicknamed "Nutcracker Man" because of its powerful jaws and large, flat teeth, did not eat nuts but instead dined primarily on grasses, according to a new study involving CU-Boulder. Credit The National Museums of Kenya. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.